GlowThis ring has an inlay of glow in the dark material. This is the type of material that is charged in sunlight or other light and it releases a light green light for hours. It is safe with no radiation like radium or tritium have. It also glows wildly under black light. Works well on a black ring. The ring can be made in three grades of titanium, black zirconium, cobalt chrome, or stainless steel. The titanium or other metal helps to protect the inlay